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Background: Anthrax is a common disease among human and livestock which is caused by Bacillus anthracis. Bacillus anthracis has two strong immunogenic proteins: Protective antigen (PA) and lethal factor domain I (LFD1) that have always been considered as vaccine candidates against Bacillus anthracis. The aim of this study is to express and purify the lethal factor domain I (LFD1) in Escherichia coli and produce polyclonal antibody against it in mice. Materials and Methods: In this experimental study, LFD1 gene was amplified with BamH I and Xho I restriction site by PCR. After isolation, the gene was cloned to the expression vector pET28a (+). This vector was transformed to E. coli-BL21 (DE3) PLysSto to express LFD1 gene. The expression of LFD1 gene was induced by IPTG. After protein purification by affinity chromatography, the produced antigen was injected into mice for four times. Then the produced polyclonal antibody in mice serum was evaluated. Results: The cloned LFD1 gene in pET28a (+) vector was confirmed by PCR, enzymatic analysis, and sequencing. The expressed and purified recombinant protein was confirmed by SDS-PAGE and Western blotting. Finally, the isolated polyclonal antibody from mice serum was evaluated and confirmed by ELISA test. Conclusion: Noticing the appropriate expression, easy purification of LFD1, and the titer of produced polyclonal antibody against LFD1 in mice due to its immunogenicity, it can be considered as a good vaccine candidate against anthrax.

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Background: Giardiasis is the most common infectious diseases of medical parasitology and public health in our country and in many countries is important. Accourding the importance of treating the disease, particularly parasite resistance to drugs. Thus, the aim of present study was investigated the effect of gold nanoparticles on Giardia lamblia cyst stage of the in vitro.

Materials and Methods: In this experimental study, Giardia cysts from contaminated fresh feces were collected and concentrated with use 0.85 M sucrose methods for isolation of cysts. Samples after counting with Noubar slide were stored at 4°C. The gold nanoparticles at concentrations of 0.05, 0.1, 0.3 mg/ml prepared and verified, the particle size was determined. The effect of different concentrations of the nanoparticles at 5, 15, 30, 60 and 180 minutes was evaluated and compared to control groups (metronidazole). Data from the study were recorded and analyzed with T-test and Chi-square by used SPSS software.

Results: The results of the cytotoxic effect of nanoparticles on the different concentration and time of Giardia lamblia cysts in vitro compared with the positive control (Metronidazole) shows mean percent of effect gold nanoparticles increased with increasing concentration and exposure time, so that the concentration of 0.3 mg/ml from 62% at 5 min to 96% at 180 min increased (p<0.05). Also, the survey results show Giardia cysts with increasing exposure time , killing effect of gold nanoparticles at a concentration of 78% in 0.05 mg/ml to 96% at a concentration of 0.3 mg/ml greatest increased (p<0.05). As a result, the concentration of gold nanoparticles in comparison with Metronidazole has the most effect gold nanoparticles at a concentration of 0.3 mg/mL, almost the same effect of Metronidazole as the drug of choice in the treatment of Giardia lamblia.

Conclusion: Therefore, the results of this study, gold nanoparticles at a concentration of 0.3 mg/ml as an effective combination for killing Giardia lamblia cysts in vitro can be used. Thus, future studies on laboratory animals (In vivo) are recommended.

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Background: Studies have shown that central cholinergic system can be effective on animal memory in objects emplacement, but there were no sufficient information about the consumption of effective substances on this system during pregnancy in novel object recognition in compared to old object and its effect on the fetus. The aim of this study is investigation of lecithin (as a source of choline) effect during pregnancy and lactation on object recognition behavior as a marker of cognitive memory in male and female rat offspring.

Materials and Methods: In the present experimental study, female rats with an average weight of 160±10 g were gavaged of pregnancy (22 days) until 21 days after the parturition by different amounts of lecithin or its vehicle. The groups were: control (without receiving any medications), vehicle and receiving lecithin with amounts 120 and 240 mg/kg. After gender segregation, at 36 days of birth offspring were trained to evaluate the recognition memory. The number of offspring in each group for each sex was 7.

Results: Results showed that consumption of lecithin 240mg/kg in female offspring was lead to increase in percentage of time spent in near of novel object in compared with vehicle group (p<0.05). While in other groups there was no difference between offspring.

Conclusion: Lecithin consumption during mother pregnancy and lactating lead to change in precognitive memory of female offspring and also sex can cause different effects of this compound in the body of an animal.